vtkInteractorEventRecorder can be used to record VTK events in a single file and replay it by pass these events to vtkRenderWindowInteractor.
Record
The following code shows how to use it to save all interactive information into a file.
We rotate the cone and switch its surface status between wireframe and flat plane by mouse and special keys.
The vtkInteractorEventRecorder object records these events into file /Users/weiyang/Desktop/record.txt
int main()
{
vtkSmartPointer cone =
vtkSmartPointer::New();
cone->Update();
vtkSmartPointer coneMapper =
vtkSmartPointer::New();
coneMapper->SetInputData( cone->GetOutput() );
coneMapper->Update();
vtkSmartPointer coneActor =
vtkSmartPointer::New();
coneActor->SetMapper( coneMapper );
vtkSmartPointer renderer =
vtkSmartPointer::New();
renderer->AddActor( coneActor );
renderer->SetBackground( 0, 0, 0 );
vtkSmartPointer renderWindow =
vtkSmartPointer::New();
renderWindow->AddRenderer( renderer );
vtkSmartPointer renderWindowInteractor =
vtkSmartPointer::New();
renderWindowInteractor->SetRenderWindow( renderWindow );
vtkSmartPointer recorder =
vtkSmartPointer::New();
recorder->SetInteractor( renderWindowInteractor );
recorder->SetFileName( "/Users/weiyang/Desktop/record.txt" );
recorder->EnabledOn();
recorder->Record();
renderer->ResetCamera();
renderWindow->Render();
renderWindowInteractor->Start();
return 0;
} record.txt:
Replay
In the following example, I used renderWindowInteractor to diaplay window, so renderWindowInteractor->Start() is put before recorder->Play(). But there is UI event loop created by renderWindowInteractor->Start(), therefore user has to close the window in order to make replaying mechanism work.
main.cpp:
//...
renderer->ResetCamera();
renderWindow->Render();
char *filePath = "/Users/weiyang/Desktop/record.txt";
vtkSmartPointer recorder =
vtkSmartPointer::New();
recorder->SetInteractor( renderWindowInteractor );
recorder->SetFileName( filePath );
recorder->EnabledOn();
recorder->DebugOn();
std::ifstream inFile( filePath );
int linesCount = std::count(std::istreambuf_iterator(inFile),
std::istreambuf_iterator(), '\n');
qDebug() << "There are " << linesCount << " lines.";
renderWindowInteractor->Start();
recorder->Play();
return 0; 
output:
There are 1145 lines.
Debug: In /Users/weiyang/Downloads/VTK-8.1.1/Rendering/Core/vtkInteractorEventRecorder.cxx, line 201
vtkInteractorEventRecorder (0x7f8f71560100): Playing
Debug: In /Users/weiyang/Downloads/VTK-8.1.1/Common/Core/vtkObject.cxx, line 886
vtkInteractorEventRecorder (0x7f8f71560100): UnRegistered by nullptr, ReferenceCount = 0
Debug: In /Users/weiyang/Downloads/VTK-8.1.1/Rendering/Core/vtkInteractorEventRecorder.cxx, line 114
vtkInteractorEventRecorder (0x7f8f71560100): Disabling widget
Debug: In /Users/weiyang/Downloads/VTK-8.1.1/Rendering/Core/vtkInteractorObserver.cxx, line 27
vtkInteractorObserver (0x7f8f71560100): vtkInteractorObserver (0x7f8f71560100): setting DefaultRenderer to 0x0
Debug: In /Users/weiyang/Downloads/VTK-8.1.1/Common/Core/vtkObject.cxx, line 150
vtkObject (0x7f8f71560100): Destructing!
